The present invention relates to a pumped shower draining device.
Various attempts have been made in the past to regulate the speed of a shower drain pump to that of the water entering the waste, such that the shower base or tray is effectively drained and does not flood. Frequently, this has relied upon an electronic flow sensor or sensors in the water supply pipe or pipes to the shower unit, and an electrical or electronic control system which matches the sensed flow rate entering the shower unit to the pumping capacity of the shower drain pump.
This method requires extensive and often sophisticated electronics control systems, as typified by the Digipump control system supplied by DLP Limited of Snugborough, Isle of Man.
This known arrangement requires flow sensors to be placed in all water supply pipes to a shower water heater. The electronics detects the output of the flow sensors through electric cable connections which must be run from the shower inlet to the electronics controller, which for various safety and regulatory reasons must be located a distance from the shower area. The electronics compares the detected flow rate to a pre-stored performance curve of pump speed and voltage applied to pumping capacity, and issues a pump motor control voltage to operate the pump, hopefully matching the pump performance to the flow rate of the incoming water to the waste.
Such flow sensors typically also require fine particulate filters on the supply line to them, due to the small clearances between internal components located in the water flow, and are precision instruments of often high cost, requiring sensitive installation, which may not always be carried out by installers.
Other known systems rely upon a flow switch to start and stop a drain pump, with various types of regulatory control electronic or electric controls, incorporating various degrees of what is effectively artificial intelligence programmed in to them as computer logic controls within embedded microprocessors or programmable logic controllers. These are often complex, expensive and of variable reliability and robustness.
The present invention seeks to overcome these problems.